1. Field of the Invention
The invention pertains to a device with a steering lock and an ogmition starter switch which can be controlled by a handle in the presence of an identification transmitter.
2. Description of the Related Art
Although the steering mechanism of the switch can be controlled by the rotation of a nondetachable handle, this control can be executed only after an identification receiver (ID receiver) in the vehicle has verified the presence of an identification transmitter (ID transmitter). This verification is accomplished by the initiation of an identification scan (ID scan). Otherwise, in the absence of an ID transmitter, the handle is blocked and cannot be turned by hand. This type of control is called xe2x80x9cpassive goxe2x80x9d or xe2x80x9ckeyless goxe2x80x9d. The ID transmitter consists of, for example, a card, which is carried by the authorized user of the vehicle. An ID transmitter of this type could also be integrated into an electronic key or into a cell phone.
Control means, which include a cam, are connected to the handle so that it can be blocked or released. After the handle has been actuated, the control means are returned by a restoring spring to a defined axial starting position. The cam has the job of properly coordinating the axial and rotational movement of the control means.
The known device of this type (DE 198 38 992 A1) requires a great deal of technical effort. Conventional steering locks and ignition switches cannot be used. The steering is locked electronically. The handle must execute not only a rotational movement but also certain axial movements in coordination with the rotation in order to move the electronic steering lock into the locking and release positions. This is cumbersome.
The invention is based on the task of developing a simple and yet reliable device of the type indicated above in which conventional steering locks and ignition starter switches can be used.
In accordance with the present invention, the device with a steering lock and an ignition starter switch which can be controlled by a handle in the presence of an identification transmitter is controlled by an ID transmitter which can be scanned by an ID receiver located in a vehicle. A control of the device includes a rotor which is constructed in part of magnetizable material. The rotor is connected to a handle in a rotationally fixed but axially mobile manner. In an axial starting position, the handle is blocked, but if the ID scanning is successful, an electromagnet is activated in order to move the rotor into an axial intermediate position. The handle can then be turned and the rotor is moved into an axial end position. The electromagnet is cut off, but a permanent magnet is activated to immobilize the motor. The steering mechanism is then released by the rotor output, and the handle can be turned in a reverse manner. First, the axial end position of the rotor is maintained and then the release position of the steering mechanism is maintained.
Because the control means in the invention consist of a rotor with at least certain areas of a material which can be magnetized, the rotor can be controlled axially by an electromagnet and held in its axial end position by a permanent magnet. In the axial starting position, the rotor is blocked, and therefore any attempt to turn the handle will fail. In this position, the rotor is also sufficiently far away in the axial direction from the permanent magnet, so that the permanent magnet does not yet have any effect on the rotor. If the ID scan is successful, current is supplied to the electromagnet, as a result of which the magnet pushes the rotor to an intermediate axial position against the force of the restoring spring acting on it. This lifts the blockade, and it is now possible to turn the handle. During this rotation of the handle, a slanted intermediate section of the cam is able to interact with the rotor. The turning of the handle, therefore, causes the rotor to arrive in an axial end position, in which the permanent magnet is now able to hold it, even after the current to the electromagnet has been turned off. The rotor can now be turned even farther, as a result of which a position in reached in which the steering mechanism is unlocked, and, in correspondence with the degree of rotation, the various other working positions of the switch are reached one after the other. This axial end position, however, remains preserved even after the rotor has been turned back in the opposite direction. During this reverse rotation, the rotor disengages from the cam and can be moved back to the home position of the switch, but the steering mechanism remains at first in its unlocked position. This does not change until after a sufficiently strong axial opposing force is exerted on the rotor, that is, strong enough to overcome the holding force of the permanent magnet and to move the rotor back into its axial starting position. Then the steering mechanism is moved into its locking position, and the rotor comes back into contact with the cam, which has the effect of preventing the handle from being turned. This interaction between the electromagnet and the permanent magnet can be executed reliably. The invention makes it possible to use conventional steering locks and ignition starter switches, which can be controlled by mechanical rotations or axial movements of the rotor output end.
Additional measures and advantages of the invention can be derived from the subclaims, from the following description, and from the drawings. The drawings present the invention schematically on the basis of an exemplary embodiment. The figures marked xe2x80x9caxe2x80x9d show all the important components in axial cross section in different operating positions, whereas the figures marked xe2x80x9cbxe2x80x9d show a plan view of only a part of the device with the housing cut in the axial direction: